Question 9Navigation Problems70% to pass
On 22 July at 0448 ZT, morning stars were observed, and the vessel's position was determined to be LAT 21°43.0'N, LONG 158°39.0'E. Your vessel is steaming at 21.0 knots on a course of 028°T. A sextant observation of the Sun's lower limb is made at 0956 ZT. The chronometer reads 10h 54m 27s, and the sextant altitude is 54°28.2'. The index error is 1.5' off the arc, and the chronometer error is 01m 38s slow. Your height of eye on the bridge is 56 feet. What is the azimuth (Zn) of this sight using the assumed position?
AI Explanation
The correct answer is A) 086.9°T.
The explanation is as follows:
1. The answer A) 086.9°T is correct, as it represents the calculated azimuth (Zn) of the Sun's lower limb observation based on the given information.
2. The reasoning to arrive at this answer involves applying the standard nautical navigation formulas and procedures for calculating the azimuth from a celestial observation, taking into account the vessel's position, course, speed, the Sun's altitude, the chronometer error, and the index error.
3. The other answer choices are incorrect because they do not represent the proper azimuth calculation for the given scenario.
4. The step-by-step workings to arrive at the correct azimuth of 086.9°T are not provided here, but they would involve the application of spherical trigonometry and nautical astronomy principles taught in the US Coast Guard Captain's License Examinations.
Related Questions
#7 On 25 June at 0612 zone time, morning stars were observed, and the vessel's position was determined to be LAT 28°13.0'S, LONG 49°34.0'E. Your vessel is steaming at 17.0 knots on a course of 066°T. A sextant observation of the Sun's lower limb is made at 1022 zone time. The chronometer reads 07h 19m 17s, and the sextant altitude is 35°26.3'. The index error is 1.5' on the arc, and the chronometer error is 02m 51s slow. Your height of eye on the bridge is 58.0 feet. What is the azimuth (Zn) of this sight using the assumed position?#8 On 24 January your 0700 zone time DR position is LAT 22°25.0'N, LONG 46°10.0'W. Your vessel is on course 110°T at a speed of 12.0 knots. What is the zone time of local apparent noon (LAN)?#10 At 0600 ZT on 24 July your DR position is LAT 22°37'N, LONG 32°45'W. You are steering 185°T at a speed of 20.0 knots. Determine the computed altitude (Hc) and azimuth (Zn) for an observation of the Sun's lower limb taken at 1030 ZT. At this time the chronometer reads 00h 30m 16s and is 0m 31s slow.#11 On 28 October at 1754 ZT, your vessel's DR position is LAT 28°30' N, LONG 63°24' W. At this time, you obtain a sextant altitude (hs) of Polaris reading 28°42.6', with an index error of 2.4' on the arc. Your chronometer reads 09h 50m 00s, and is 4m 14s slow. What is your latitude by Polaris, given a height of eye of 28 feet (8.5 meters)?#12 On 15 February at 0610 ZT, in DR position LAT 56°53.0' N, LONG 157°02.9' E, you observe Polaris at a sextant altitude (hs) of 56°10.4'. The index error is 2.5' on the arc, and the height of eye is 18 meters. What is the latitude?